Internal combustion engine control



go to the suction type of superchargers.

Patented June 18, l 1

UNITED STATES PATENT OFFICE 1mm Gregg. Caldwell, and menus Daalder,- Paterson, ,N. 1., assignors to Bendi; Aviation Corporation, South Bend, Ind., a corporation of Delaware Application December 21, was. Serial a... 241.12!

14 Claims. (0. 1235119) This invention relates to supercharged internal combustion engines and more particularly to improvements in'control mechanism for controlling the supercharging action.

Prior to the present invention the art included supercharger control systems based upon the concept of employing manual control-of the supercharger for only a partial throttle'control oi the carburetor, so that beyond the point where manual control ceases the controlof the carburetor throttlelsupercharging action) is entirely and exclusively automatic. The present invention utilizes a different concept,,nam'ely, the concept of permitting full-range manual'control over, and

1 above the automatic control at all times and under all circumstances, including the contingency of complete non-functioning of the automatic. control, In this connection a featureof the invention (applicable to either the suction type '50 or the pressure type of supercharger system) is the provision of means for looking out the automatic control'elements at the will of the operator, with the manual control continuing to function independently of any movement of said autou matic control elements -even during the actual process of looking out said automatic elements. This feature of the invention contrasts with the prior art modes of operation including those heretofore applied to the pressure type as well as (In using the term "pressure type it is understood that we refer to the type wherein the supercharger is driven by engine exhaust gases rather than'mechanically, and draws air directly from the atas mosphere, rather than from the carburetor.)

with particular reference to the automatic control elements themselves. as distinguished.

from the complete system, the invention further contemplates use of a pressure actuated servo- (0 element including a piston whose operating fluid is supplied to opposite sides of the piston under the control-of a valve adapted to be shifted to a predetermined position by manual means (tov bring about one phase of the "looking out" above 45 referred to) as well as'being shiftable by'movement of. an expansible hollow element (herein shown as a bellows) whose interior is in direct communication with the intake manifold of the engine and therefore reflects the'pressure condi- 50 thus prevailing therein. 'A further feature is the provision of manual control of manifold pressure by controlling the degree of resistance offered to expansion of the expansible hollow el inent, said manual control being'herein disclosed as incorprinted in the same manual control linkage as that which governs the, looking out ofthe piston,

although-(as. will appear). it may be separate and distinct therefrom, and operated independently 1 thereof. These and other objects and features of the invention are pointed out in the following description in terms of the embodiment thereof which is shown in the accompanying drawing.

It is to be understood, however, that the drawing is for the purpose of illustration only, and is not designed as a definition of the limits of. the invention, reference being had to the appended claims for this purpose.

In interpreting the appended claims, where they refer to a supercharger, they are to be construed as including application of the invention to any known type of supercharger, however driven, and to any type of throttle controlled englue; and where the claims are directed to less than all of the elements of the complete system disclosed, th y are intended to cover possible uses 5 serves to connect carburetor I with the combustionspaces (not shown) of the engine, by way of supercharger 8 and supercharger inlet I; the throttle l0 being pivotally mountedin said inlet passage 9, and shiftable to any position between fully open and fully closedin response to corresponding movement of the linkage leading thereto. This linkage includes amanuallyshiftable throttle control lever ii and a bell-crank l2 whose central pivot it passes through the end portion ll 'of a rod l5 whose opposite end is integrated with a piston I6 constituting the servov element above referred to. a As shown the servo-piston it is slidable in a cylinder "having two ports II and I! on opposite sides. of said piston, through which ports fluid is caused to flow whenever the correspondingly spaced covering portions 2i and 2!, respectively, of the slide valve 23 are not in flow inhibiting relation thereto.

The operating fl uid u may be oil received from the engine oil supply by way of pipe 28 and returnable to the engine oil sump by way of outlet '2 or 2!, as the case may be, whenever a shifting ofthe control valve '23 from its neutral position causes one of said inder l1.

The disclosed embodiment of manifold pressure actuated means acting upon control valve 23 tocause supercharger. regulating (throttle shifting) movement of the servo-element It will now be described. An arm 3| extendsin rigid fashion from one end of. valve 23 and connects to a plate 32 interposed between a pair of hollow, flexiblewalled cylinders or bellows l3 and 34, the former being sealed under vacuum or under a predetermined pressure-although a vacuum or near vacuum is preferred. Bellows 34, on the other hand, has direct communication with intake manifold 5 by reason of conduit 36 leading thereto, and also contains a tube 31 and spring 38 having one end thereof fastened to the end portion 39 of the tube 31; the opposite end of spring 38 being secured to the end portion or collar 4| of. a rod 42 constituting part of the manually operable means 64, I4 and 84 for locking out the piston 16, and also constituting a means for varying the tension imposed upon spring 38 and thereby varying the degree of opposition to left.-

ward movement of control valve 23 under the urge of the manifold pressure operating upon the bellows 34 in the direction counter to the pull of spring 38. The initial spring tension depends upon the setting of screw Si in the threaded bearing or nut constituting the above-described end portion 39 of the tube 21; but from this initial adjustmentthe tension is variable by manually shifting the manifold pressure selecting linkage 64, 14, 8'4, 42. The range of movement of this linkage 84 to 42 (as indicated by the arc A-B-C-D in the drawing) thus determines the maximum and minimum limits of manifold pressure obtainable by the automatic means constituted by servo-piston I8; it being understood that the piston I6 can move only in response to a shifting of the control valve 22 in either direction from its central position, and that the action of the control valve 23 is in turn governed by the extent to which spring 38 or the existing manifold pressure may temporarily overpower the other and thus cause a temporary shifting of the valve 23 from said central position.

'The locking out of the servo-element l6, when desired, is accomplished-ineither' one (or both) of two ways: first, by the establishment of a fluid lock, which involves manually shifting the control valve 23 to a position wherein the piston l6 moves to the innermost position and remains there due to the inability of the valve to reverse while the manual restraint thereon remains eiIective; and secondly, by the establishment of a mechanical lock in, the form of latch 61 movable into position to engage groove 62 in the piston rod whenever manually shifted cam 63 (forming paitof manifold pressure selecting linkage 64 to 42) occupies a position adJacent either extreme of its range of movement, said extremes of the cams movement being so set that one extreme coincides with the fluid lock establishing position ofthe valve shifting rod 42; the result of such coincident settings being, of course, to make it possible to'have both the fluid lock andthe mechanical lock effective in such manner that the latter supplements and confirms the former.

The manner in which these twolocking actions areefiected will now be described in greater detail. First as to the fluidlock, thiscan not occur until the movement of .rod 42 is suflicient to bring the collar 4| thereof into abutting engagement with the end of tube 31. After such abutting .outlets to receiveoil discharged from the cylengagement occurs, further movement in the same direction will result in corresponding shifting of thevalve 23 (to the position shown in the cover outlet l8 and will thus remove all oil pressure resistance to movement of piston It to its innermost position, under the urge of the oil pressure on the outer side of the piston, into which oil is now being supplied by way of ports 20 and is; the movement of the piston to its innermost position being further assured by rea-, son of the additional pressure exerted by spring 40 upon the outer side 'of the piston.

Now, as ,to the mechanical lock'(latch) this does not actually take effect until two actions concur: first, the'positioning of controlling cam 43 (manually operated by the pressure selecting means 64) in either of the end zones (A-B or -C-D) of its range of movement, the entire range of movement being that indicated by the ,arc AD as a whole; and secondly, the completion of the inward stroke of the piston l6, whereby groove 62 of the piston rod arrives in position to receive latch BI and be held firmly thereby, by reason of the pressure exerted in the locking direction by spring 44. These two actions may, of course, be dissimultaneous; that is,'the con- -.trolling cam 83 may be in either end zone prior to movement of groove 62 to the latch receiving positiombut in such event the latch will bear frictionally upon the adjacent portion III of the sliding rod l5 until the groove 02 arrives opposite the latch, whereupon the latter will snap into locking positionassuming that in the meantime the operator has not shifted control cam 83 to an intermediate (B-C) positionand thereby provide positive restraint against movement of. the piston it, over and above the resistance to such movement that is due to the pressure of the oil and the spring 40 upon said piston, in this "fluid lock position of valve 23. With the piston thus locked the operator may exercise full manual control over the throttle by manipulation of throttle lever II, as above described.'

During periods when there is no lock-out of the rod IS, the throttle may be shifted by either the manual means II or by movement of the piston, for-as in the prior art-the bell-crank I2 is of the floating type, with both its central pivot l3 and its upper pivot "a serving alternately as fulcrums about which rotation may occur; the pivot I! being the fulcrum wherein manual actuation occurs, and the pivot Ila when automatic (piston induced) actuation occurs. In this connection it is to be understood that the levers II- and 64 are held, frictionally or otherwise,-in whatever position they are caused to occupy, and remain in such positions until manually shifted. 1

What is claimed is:

1; The combination with an internal combus 'tion engine throttle, of fluid pressure actuated means for shifting said throttle, said shifting means for shifting said throttle," said' shifting means including a'control valveja piston, a rod subject to a fluid lock tending to hold it at one' and a lever linkage responsive to changes in the engine's manifold pressure, and said piston being endof its stroke, means for swinging said lever about one end of said rod to shift said throttle independently of any change in manifold pressure, manual means for shifting said control valve tion engine having an air and fuel inlet conduit,

of a servo-motor to control pressure in said conduit, means responsive to a change in the pressure-in said conduit for causing pressure controlling movement of said servo-motor, means including a spring opposing the conduit pressure.

- as a servo-motor actuating means, and a handmanipulable linkage for varying the amount of opposition exerted by said spring.

.4. The combination with an internal tion engine having an air and fuel inlet conduit, of a servo-motor to control pressure in said conduit, means responsive to a change in'the pressure in said conduitfor causing pressure controlling movement of said servo-motor, means including a spring opposing the conduit pressure as a servo-motor actuating means, a hand manipulable linkage for varying the amount of "opposition exerted by said spring, and a second hand-manipulable linkage for exclusively controlling pressure in said conduit when said firstnamed linkage is in a predetermined position.

5. The combination with an internal combustion engine throttle, of fluid pressure actuated means for shifting said throttle, said shifting means including a piston, a rod and a lever link-'- age displaceable as a unit byv changes in the engines manifold pressure, means for swinging said lever about one end of said rod to shift said throttle independently of any change in manifold pressure, means for locking said piston, said locking means including a control valve control- .ling. delivery of' pressure fluid to said piston, manual means for shifting said control valve to piston locking position, and a second look for f the piston in theform of a latch engageable with said rod, said latch being releasable in response tm'movement of said manual means out of the position corresponding to piston; locking position.

6. The combination with an internal combustion engine having sash and fuel inlet conduit in which the pressure tends to vary as the altitude varies, of means to control the pressure in said conduit, said means including a piston rod, a piston, and a valve controlling delivery of pressure fluid to said piston for movement of said rod, manual means for shifting said valve,

and means engageable with said rod to lock the piston against movement, said locking means heing operablein response to a predetermined de- 'gree of movement of said manual valve shifting means; I

I. Thecombination with an internal combustion engine having an air and fuel inlet conduit in which the pressure tendsto vary as the altitude varies, of means to control the pressure in said conduit-,said means including a piston rod,

apiston, and a valve controlling delivery of' pressure fluid to said piston for movement of said rod.'manual means for shifting said valve, means .15

combusrod, fluid pressure responsive'means for shifting said valve in one direction, means opposing said fluid pressure responsive means, manual means for increasing the effectiveness of said opposing means, and a latch engaging said piston rod in response to a predetermined degree of movement 4 of said manual means.

8. Thecombination with an internal combustion engine having an air and fuel inlet conduit in which the pressure tends to vary as the alti-, tude varies, of means to control said conduit pressure, said means including a piston having an extension, locking means'therefor including a latch engageable with said piston extension,

. means constantly urging said latch to latching position, and manual means restraining said latch and preventing its 'movementto latching position so long as said manual means occupies any position within a predetermined; zone.

9. The combination with an internal combustion engine having an air and fuel inlet conduit ,in which the pressure tends to vary as the altisure, said means including a piston "having an extension, locking means therefor including a 'tude varies, of means to control said conduitpreslatch engageable with said piston extension, v

means constantly urging said, latch "to latching position, and manual means restraining said latch and preventing its movement to'latching position so long as said manual means occupies any position with a predetermined zone located between two additional zones-constituting additional parts of the complete range of movement of said manual means.

10. The combination with. an internal combustion engine having an air' and fuel inlet conduit in which the pressure tends to vary as the alti-' tude varies, of means to control said conduit pressure, said means including-a piston having an extension, locking means therefor including a latch engageable with said piston extension,

means constantly urging said latch to latching position, manual means restraining said latch and preventing its movement to latching position so long assaid manual means occupiesany position with a predetermined zone, and means on said piston extension for delaying effectiveness of said latch until said piston reaches a predetermined position in its stroke.

11. The combination with an internal combustion engine having an air and fuel inlet conduit in which the pressure tends to vary as the altitude' varies, of means to control said conduitpressure, said means including a piston having an extension, locking-means therefor including a latch engageabe with said piston extension, means constan y urging said latch to latching position, manuaimeans restraining said latch" and preventing its movement to latching position so long as said manual means occupies any position within a predetermined zone located between two additional zones constituting additional parts of the complete range of movement of said man-' ual means, and'means on said piston extension for delaying effectiveness of said latch until said piston reaches a predetermined position inits stroke.

12. The combination with an internal combus-j tion engine having an air and fuel inlet conduit in which the pressure tends to vary as the altitude varies, of means to control said conduit pressure, said mesm including a piston -rod,.ar

piston, and a valve controlling delivery of pressure fluid to said piston for movement of said tion engine having an air and fuel inlet conduit in which the pressure tends to vary as the altitude varies, of means to control said conduit pressure, said means including a piston rod, a piston, and a valve controlling delivery of pressure fluid to said piston for movement of said .rod, manual means for shifting said valve, and means engageable with said rod to lock the piston against movement, said locking means being operable when said valve is in a position causing unbalanced fluid pressure on opposite sides oi.

said piston.

14. The combination with an internal combustion engine having an air and fuel inlet conduit in which the pressure tends to vary as the altitude vvaries, of means to control saidconduit pressure, said means including a piston rod, a piston, and a valve controlling delivery of pressure fluid to said piston for movement of; said rod, fluid pressure responsive means for shifting said valve in one direction, a spring opposing "said fluid pressure responsive means, manual means for increasing the opposing force of said spring; and a latch engaging said piston rod in.

response to a predetermined degree of movement of said manual means.

DAVID GREGG. RICHARD DAALDER. 

